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davin
Sep 9, 2006, 07:20 PM
So I bought a 1992 honda civic DX auto and after a week of buying it, it crapped out on me. It would crank, but would not fire up. Immediately I began troubleshooting. I checked for spark and there was none when I grounded the plugs against the frame several times while my friend cranked it. Next I checked for fuel to the fuel rail, there is fuel flowing when cranked. Also, my valvetrain moves when cranked so my belt is not broken. Everything is connected also.

There was no spark so I replaced it with a new distributor from autozone and it started right up after one crank. The next day I went to start it, and continued like last time; just cranked and would not fire. I exchanged the part from autozone and it still would crank, but not fire up.

I went to eBay and purchased an ECU from a good working Civic DX automatic that was wrecked. The sellers feedback was 100% and assured me the ECU is in working order. Still nothing, just the solid CEL with no clicking from the main relay whatsoever.

Next my determination was the main relay. I had all the diodes soldered and put back in, still nothing. Next I went to Honda and purchased a new main relay with the part numbers matching and it still would not click.

All the grounds are secure and ground properly from the ground wires (the tranny ground, the battery ground and also the engine ground from the valve cover), I get 12v from the battery and I cannot determine what is wrong with my civic. I really need to get this car running and I have spent $500 so far and I am at a total loss and I have no where else to turn. I am an aircraft mechanic for the Navy so I have a good comprehension as to what I am doing. Please help :-/

TxGreaseMonkey
Sep 9, 2006, 08:01 PM
If you turn your ignition ON, the Check Engine Light, on a properly running Honda, should come on and then go off after 2 seconds. During this time, you should hear the fuel pump run. If the Check Engine Light does not come on and then go off, focus on the main relay, ECM, and ignition switch.

My hypothesis is that your ECM is bad. Run a simple "K-Test":

Disconnect the MAP sensor connector from the MAP sensor. Turn ignition ON and check for 5 volts between the right female reference wire socket (+) and the main ECM ground on the thermostat housing. Really press the black test lead into the ground. If you don't have approximately 5 volts, then your ECM is likely bad. Remember, the ECM is nothing but a giant "power transistor," whose job it is to provide the proper voltage to a host of sensors (transducers) under constantly changing conditions. The confirming test is to turn the ignition switch OFF, disconnect the D harness to the computer, turn the ignition switch ON, and measure the voltage between computer pins D19(+) and D21(-). If there is less than approximately 5 volts, substitute a known good ECM. If you have approximately 5 volts between D19 and D21, repair an open between the ECM and YEL/GRN reference wire going to the MAP sensor.

Most of these "crank but won't start" situations on Civics are main relay, ICM, coil, or ECM related. A few have been caused by bad CYL, CYK, or TDC sensors in the distributor. If your ECM checks out OK, then I would suspect your ICM (igniter), since you just installed a new main relay. A final item to check out is the Manifold Absolute Pressure (MAP) Sensor, which is the "key" sensor on Hondas. It controls timing (similar to the old vacuum advance on distributors) and air/fuel mixture, depending upon manifold pressure changes. Like any transducer, it converts energy from one form to another. Here, it converts throttle body vacuum pressure changes into fluctuating electrical current signals to the ECM. If this sensor does not receive the proper voltage from the ECM, you will experience catastrophic ignition and fuel system failure.

My experience with Hondas has been main relays, ICMs, coils, and ECMs should be replaced proactively after 10 years or 120,000 miles, whichever comes first. Distributor bearings will likely fail around 95,000 miles.

davin
Sep 9, 2006, 08:11 PM
Do I have to find someone to crank the car while I do this or can I just turn the ket to the couple clicks ahead?

davin
Sep 9, 2006, 08:16 PM
I suspect your ECM is bad. Run this simple test:

Disconnect the MAP sensor connector from the MAP sensor. Turn ignition ON and check for 5 volts between the right female reference wire socket (+) and the main ECM ground on the thermostat housing. Really press the black test lead into the ground. If you don't have approximately 5 volts, then your ECM is bad. Remember, the ECM is nothing but a giant "power transistor," whose job is to provide the proper voltage to a host of sensors (transducers) under constantly changing conditions.

I also read your other informative post about how your car did not start because of your map sensor. I was thinking it could have been this. Did you buy a new one or was it just the connection?

davin
Sep 9, 2006, 08:19 PM
Crap, stupid me just realized that I never disconnected my battery when I swapped ECU's... do you think I fried the working ECU when I connected it to the harness?

TxGreaseMonkey
Sep 9, 2006, 08:49 PM
Yes, you have to disconnect the negative battery terminal or you can wreck the ECM.

Only replace the MAP Sensor as a last resort because they usually are very reliable and they cost $225. I ended up buying a new one.

TxGreaseMonkey
Sep 9, 2006, 08:56 PM
do i have to find someone to crank the car while i do this or can i just turn the ket to the couple clicks ahead?

I not sure of your question.

TxGreaseMonkey
Sep 9, 2006, 09:39 PM
Once you get your Civic running again, be sure to change all of the fluids. I would use Valvoline SynPower Brake Fluid and flush the whole system. Also, I would take a battery squeeze bulb and partially replace some the power steering fluid. I would also drop and clean the transmission pan, change the filter, and replace fluid with either Mobil 1 Multi-Vehicle Synthetic ATF or Amsoil Universal Synthetic ATF. I believe your Civic requires a Dexron II rated fluid. I run Mobil 1 5W-30 synthetic engine oil with a Purolator PureOne filter in my 1993 Civic DX. Finally, I would change the antifreeze with a 50/50 mixture of antifreeze and distilled water. A well-maintained Civic can last 350,000 miles.

davin
Sep 9, 2006, 09:53 PM
So after doing all that, there is absolutely no power coming from d19 and d21 nor is there any power from the map sensor wires to the ground connecting to the tranny. I have swapped out both ECUs that are compatible with my car furthermore.

My assumption is that there is no power going to the ECM, but the strange thing is that there is 12v coming from the battery.

It is not the dizzy because the complete unit was replaced along with a cap and rotor with spark plugs and all.

I am in the barracks with an aircraft electriciansmate and he cannot find anything either :-/

davin
Sep 9, 2006, 09:56 PM
I am not getting power to terminals d19 and d21 nor am I getting power from the map sensor to the ground running from the tranny. However I am getting a full 12v from the battery.

My conclussion is that there is no power running to the ECM :-/

davin
Sep 9, 2006, 09:58 PM
The thing that really stinks about this is, I have only had it about a week before it crapped on me. I bearly gave it any love :-(

TxGreaseMonkey
Sep 9, 2006, 09:59 PM
The main relay controls power going to the ECM.

http://www.tegger.com/hondafaq/mainrelayoperation/badmainrelay.html

TxGreaseMonkey
Sep 9, 2006, 10:12 PM
i am not getting power to terminals d19 and d21 nor am i getting power from the map sensor to the ground running from the tranny. however i am getting a full 12v from the battery.

my conclussion is that there is no power running to the ECM :-/


When you checked for 5 volts between D19(+) and D21(-), did you have the rest of the harness connected to the ECM and the negative battery terminal connected, the ignition ON, and testing at the "male pins" on the ECM (not on the D connector)?

TxGreaseMonkey
Sep 9, 2006, 10:35 PM
The solution is going to be something major, not some remote "possibility." The Check Engine Light has to go out for your Civic to start. If it stays on, then there won't be any spark. Likewise, a dead main relay = no spark. I still think the Check Engine Light won't go out because the ECM is bad.

Again, if the CEL will not go out, check the ignition switch, main relay or ECM.

TxGreaseMonkey
Sep 10, 2006, 05:54 AM
Two additional things to check:

. All under-hood and under-dash fuses. Use your DMM. Pay particular attention to under-hood fuse #31, which is a 7.5A fuse to the ECM. There are four fuses in a row, along the back of the fuse box. This one is located second from the left and, if removed for 10 seconds, will erase any stored DTCs and reset your ECM.

. Main ECM ground. As mentioned above, it is located on the thermostat housing. Remove and examine the 3-wire brass ground, clean with 240 grit abrasive cloth, and apply dielectric grease.

To recap, you replaced the distributor (remanufactured), which had new igniter, coil, and sensors; the main relay (Honda); and the ECM (used)? Or, did you return the distributor to Autozone, since it didn't solve the problem?

davin
Sep 10, 2006, 12:11 PM
Two additional things to check:

. All under-hood and under-dash fuses. Use your DMM. Pay particular attention to under-hood fuse #31, which is a 7.5A fuse to the ECM. There are four fuses in a row, along the back of the fuse box. This one is located second from the left and, if removed for 10 seconds, will erase any stored DTCs and reset your ECM.

. Main ECM ground. As mentioned above, it is located on the thermostat housing. Remove and examine the 3-wire brass ground, clean with 240 grit abrasive cloth, and apply dielectric grease.

To recap, you replaced the distributor (remanufactured), which had new igniter, coil, and sensors; the main relay (Honda); and the ECM (used)? Or, did you return the distributor to Autozone, since it didn't solve the problem?

I still have the remanufactured dizzy along with a new cap/ rotor with new plugs, the working ECM from a wrecked civic, a new main relay from OEM Honda and still the CEL light stays on and there are still no clicks from the main relay and everything is installed correctly.

I used the fluke to get a reading from the 3 pin MAP sensor connection D19 (yellow/ green) and D21 (green/ blue) and had no signs of a reading when the ignition was on, but not cranked. I don't feel comfortable cutting the wires from the D-Harness (looking at the ECM, the D-Harness is the mid size connector and D19 & D21 are the two most top right connections all the way at the end).

I really do not think the ECM is bad because I have two P06 computers that both register the same results. I also talked to several other people that I work with in the navy to see if not disconnecting the battery would short the computer, people said it was highly unlikely. Another person, a highly skilled aircraft mechanic that does inspections for quality assurance (these are the most knowledgeable people mind you) and he said he fixed his accords ECM and dizzy without disconnecting the battery and it worked.

Also the engine is TDC (top dead center), meaning that the cams line up with the piston... and since the cam is keyed to the dizzy (distributor), it will fire in the correct order (unless you have your spark plugs all backwards and won't fire right). Furthermore, the valvetrain does move when I crank it from taking off the oil cap and looking for the valvetrain to move when cranked.

I am bringing along an aircraft electriciansmate with me to look at my car. This is way beyond my level of electrical engineering and see if his professionalism hands on will do. Also, I will take off all the grounds and take a wire brush to all the connections to see if that will help. Also I will disconnect the battery and reconnect all the connections that I have touched, also checking all the fuses, do all the groundings as stated above, reconnecing the battery and see if that will do anything. I need this car by tonight because I have class to go to and I need college in me to keep me out of trouble :-/

I really appreciate all your help and I tried applying all my knowledge and processes in case people try and Google this with a no start, no spark problem from a Honda Civic.

davin
Sep 10, 2006, 12:32 PM
After talking with the aircraft electrician, he said it sounds like a ground issue somewhere. Especially if when I purchased a new dizzy, it fired up and the next day it didn't. Then going back to autozone for an exchange to only crank again. So we are going to do that and also the fuses while the battery is disconnected. Hopefully that will help.

davin
Sep 10, 2006, 12:41 PM
I also did not see an alarm that turns off the ignition anywhere, so I ruled that out as well. Also noted, they said not disconnecting the battery would not short out my ECM.

TxGreaseMonkey
Sep 10, 2006, 12:53 PM
You have had some introduction to Honda Civics. In my mind, your Civic should run. Apparently, you have an "open" somewhere or the ignition switch is bad and the ECM is not getting power. Thanks for your response, professional attitude, and service to your country. God bless.

TxGreaseMonkey
Sep 10, 2006, 01:16 PM
The D-Harness is the molded connector on the right with 22 sockets.

.. .
.. .

As you look at the pins on the ECM, D19 and D21 are the last two pins on the bottom row.

davin
Sep 10, 2006, 01:36 PM
If the car turns over, then would that rule out the ignition switch right? As I am at work now, I am contemplating what is wrong and asking others some questions. The only reason I think the pins are not throwing and voltage is because there has to be an open somewhere. Personally, I feel it has to be a ground because my wire harness looks great. I will keep you posted as to what the outcome is with mechanics looking at my car after work. Actually, I have to go now because the pilots need something and the bird is rotating and ready to fly...

TxGreaseMonkey
Sep 10, 2006, 02:16 PM
No. "ON" is one circuit through the main relay and "START" is a different circuit. ON and START have different contacts in the starter switch. Power flows from the battery, through the ignition switch, to the under-dash fuse box, and to the ON or START circuit of the main relay.


Thought: You have no power to the ECM because the first relay in the main relay is not being energized.

The main relay actually contains two individual relays. One relay is energized whenever the ignition is on which supplies the battery voltage to the ECM, power to the fuel injectors, and power for the second relay. The second relay is energized for 2 seconds when the ignition is switched on, and when the engine is running which supplies power to the fuel pump.

Test: Turn ignition to ON and listen for the "click" of the first relay.

davin
Sep 10, 2006, 06:47 PM
Nothing, I have nothing. After all my hard work I get nothing. I had the Chief Aircraft Electriciansmate help me, he knows his stuff and fixes aircraft, still rotating mind you while there is Navy Seal Team awaiting insertion, before they take off and I work right along side of him. I am at a complete loss, I have no car to get me around, I need a car to get to school tomorrow and I am ready to hit the bar to get ****faced via the bus.

I checked every freaking fuse, I pulled all the grounds, took a wire brush to the grounds along with the frame and bolts, I also pulled all my connections to make sure there was nothing inside blocking continuity also assuring that the pin was aligning with the connector to complete the electrical path too.

After all that, I put the key in, I only hear one click from the key switch, no two aditional clicks from the relay and I still freaking get the solid Check Engine light. I am going to check all my fuses again and try again. If that does not work, I am hopping on the bus to the bar. I bought this honda for reliability so I can actually focus on school and keep my mind clear, I never thought it would bring me down to this level. I really don't feel like burning all my paycheck on this car, I am totally lost. I don't get paid a lot and I do not want to spend my hard earned money I got saved from repairing aircraft in balad iraq all while getting mortered to just fix a Honda of all things.

davin
Sep 10, 2006, 07:04 PM
The only is, it has to be the ignition switch

TxGreaseMonkey
Sep 10, 2006, 07:11 PM
I'm sorry for your frustration, especially when you are trying to do the right thing.

See if it could be the throttle position sensor. Turn the ignition switch ON, disconnect the 3P connector to the Throttle position (TP) sensor, and wait several minutes and see if the CEL goes out. If the light goes out, replace that sensor.

Now, see if it could be the MAP sensor. Reconnect the TP Sensor. Turn the ignition switch ON, disconnect the 3P connector to the MAP Sensor, and wait several minutes and see if the CEL goes out. If the light goes out, replace the MAP sensor.

davin
Sep 10, 2006, 07:36 PM
Nope, tried them both and the CEL still stays on along with the oil light (the only two lights that are on). Also with the ignition switch, I am leaning toward this. I am researching on how to test for this...

davin
Sep 10, 2006, 07:44 PM
I doubt it is the ignition switch because all the article symptoms I read are pointing that the car would be fine, and randomly die on the road. My car cranks, with out the replays clicking, the CEL staying on and no spark.

TxGreaseMonkey
Sep 10, 2006, 07:48 PM
Never give up!

If the CEL stays on, the causes are ignition switch, main relay (which we know is new) or the ECM. I agree that the ignition switch is not most likely. I still feel that it's the ECM. I like Cardone remanufactured ECMs, with a lifetime warranty, from O'Reilly Auto Parts. Get them to match Advance Auto Part's price and get the lifetime warranty. Put a new one in (10 minute job) and I bet your car starts and runs like a top. Remember to disconnect the negative battery cable before installing. If it's not your ECM I will be greatly surprised. I don't believe that it will be a connectivity problem--I haven't seen it yet on Hondas. They have good wiring and connectors. It's the core electrical stuff that wears out--ECMs, main relays, ICMs, and coils. Those are the usual culprits I've seen. To me, the odds are 90% that it's the ECM. I've wasted lots of time checking connectivity issues over the years--I was usually barking up the wrong tree. These Honda ECMs are not bullet-proof. Heat, vibration, and water trashes them. I've been told the electrolytic capacitors on the 1989-94 Civic ECMs are prone to leaking.

davin
Sep 10, 2006, 08:01 PM
I do not plan on giving up, I just am really low on money right now and I do not have a lot to work with other then the money in savings for which I need in case of emergency.

There is not O'Reily autoparts stores around me. I am going to shop around for the cheapest ECM covered under warranty :-D

Thank you for all your help. I really appreciate everything you do for others helping them as well as myself.

davin
Sep 10, 2006, 08:15 PM
First thing tomorrow is me hitting up kragen auto parts to get an ECM with a 1 year warranty for $260.

TxGreaseMonkey
Sep 10, 2006, 08:22 PM
You are a great American and it is I who appreciate everything you are doing to protect this nation, during this very difficult period in our history.

TxGreaseMonkey
Sep 10, 2006, 08:31 PM
My bet is you are stationed in San Diego. I know Kragen Auto Parts is all over California. I used to work at the Pacific Missile Test Center, Point Magu, CA.

davin
Sep 11, 2006, 03:40 PM
No one in the san diego area has any in stock. I tried Kragen, Auto Zone and Napa :-/

TxGreaseMonkey
Sep 11, 2006, 04:37 PM
davin, go to the site below, order the computer, and request 2 day delivery.

http://www.partsamerica.com/ProductList.aspx?PartType=248&PTSet=A&SearchFor=Engine%20Computer

TxGreaseMonkey
Sep 11, 2006, 05:13 PM
Is the original ECM Honda Part No. 37820-P06-A50?

Try:

http://www.partsamerica.com/ProductList.aspx?PartType=248&PTSet=A&SearchFor=Engine%20Computer
Or
http://rockauto.com

davin
Sep 11, 2006, 06:54 PM
OK, so all day today (I have off from work from doing work-ups from the weekend) I have been working on this car. I have a co-worker who has a 1993 honda civic LX automatic and I took out his ECM from his car and put it in mine. I disconnected the battery and everything and when I went to turn the key, no clicking from the relay and the CEL still stays on. Then when I put the same ECM into his civic, it fired right up!! Now I am thinking it could be the ignition switch, I have no other ideas :-/

TxGreaseMonkey
Sep 11, 2006, 07:19 PM
Only thing else I can think of is some sort of interlock associated with the transmission or antitheft device. Pretty unbelievable.

Did your Electriciansmate look at it?

davin
Sep 11, 2006, 07:26 PM
Yeah, he really could not figure anything out because all my grounds are good, my wire harness looks good, and my battery is at 12volts. He is also ASE certified I might add. He took a fluke to a lot of the goodies and everything read fine. We where also going to try the 12volt light bulb test, but we forgot it :-/

I am about to look at the switch right now and see if it looks pitted or anything. I think it may be that because my low beams do not work as well (the bulbs are new and the fuses are good, I was thinking it was the switch, but it could be an open leading from the ignition switch). This is the only thing I can think of :-?

TxGreaseMonkey
Sep 11, 2006, 07:34 PM
Check these sites out on Honda ignition switches:

http://www.tegger.com/hondafaq/ignition_switch/index.html

http://techauto.te.funpic.org/ignitionswitch.php

davin
Sep 11, 2006, 07:54 PM
*goes out and hotwires the car*

It has to be that because it says that if you do not hear the clicking sounds of the car, then it is the ignition switch!

TxGreaseMonkey
Sep 11, 2006, 08:08 PM
Victory is within sight.. . Full speed ahead!

davin
Sep 11, 2006, 08:20 PM
Bingo, there is no continuity at the switch, thus not giving power to the ECM which is why I was not getting a reading at all with the MAP Sensor! Also the main relay is not clicking because there is no power to that either. It would be awesome if this was the answer as to why my low beams on my civic don't work either rather then the switch. The really crappy thing is, I have no money for the ignition switch that I can spare :-/

TxGreaseMonkey
Sep 11, 2006, 08:23 PM
The article shows how you can repair them.

davin
Sep 11, 2006, 08:31 PM
At work on Wednesday I will have the electricians resolder all the connections to get it running like new :-D

Hopefully this will work and will allow me to be at school other then taking the trolly there and back everyday

TxGreaseMonkey
Sep 11, 2006, 08:34 PM
Yes, that would be awesome. If there's pitting, see if they could use low temperature silver solder to repair it.

TxGreaseMonkey
Sep 12, 2006, 10:49 AM
I'm sure you are removing the ignition switch today. How does it look?

davin, here's a posting on air conditioners I put together a few weeks ago. You might find it interesting and helpful, at some point:

https://www.askmehelpdesk.com/cars-trucks/recommended-air-conditioner-maintenance-32101.html

I have really enjoyed working with you and hope things settle down for you now.

davin
Sep 12, 2006, 03:12 PM
NOTHING!!

I borrowed some money from some people at work and have to pay them back. I went to a junk yard and bought a pretty decent ignition switch that looks pretty good when I opened it and when I rewired it, connected the battery and everything, the engine light was on and no clicking!!

I have no ideas left, this is probably something so stupid that I am probably not going to forgive myself like if I accidentally kicked a cord from under the dash and knocked it loose or something. I really don't know, I have tried everything. What the hell was it when I installed a new dizzy and it started right up. It has to be something. I now have a farmers tan from getting this car running... I am at a total loss!

TxGreaseMonkey
Sep 12, 2006, 05:42 PM
Was the ECM from your buddy's Civic that you tried the exact one for your car? Your car is a 1992 Civic DX, with what engine? Is it the D15B7 engine?

davin
Sep 12, 2006, 05:50 PM
No, his was a P06-L50. I went on Honda-Tech and they said that as long as it is a P06 automatic, that is will be good to go.

TxGreaseMonkey
Sep 12, 2006, 05:54 PM
What Honda Part No. was on the original ECM in your Civic?

TxGreaseMonkey
Sep 12, 2006, 06:09 PM
Inspection of main relay and relay harness:

Disconnect the main relay connector. Check for continuity between BLK terminal 2 and body ground. Is there continuity? NO--repair open in BLK wire between main relay and ground located at thermostat housing. YES--measure the voltage between YEL/WHT terminal 1 and body ground. Is there battery voltage? NO--replace ECM (15A) fuse in the under-hood fuse/relay box; repair open in the YEL/WHT wire between the main relay and the ECM 15A fuse.

davin
Sep 12, 2006, 06:16 PM
What Honda Part No. was on the original ECM in your Civic?

P06-A51

TxGreaseMonkey
Sep 12, 2006, 06:40 PM
After you run the main relay harness tests, I'm pretty much out of ideas. My only thoughts are if you verify power is getting to terminal 1, on the main relay connector, then I would call your local Honda parts department and see if anything other than a 37820-P06-A51 will really work.

Here's a pretty good overview:

http://techauto.te.funpic.org/index.php?content=ECU

TxGreaseMonkey
Sep 12, 2006, 06:54 PM
repair open in the YEL/WHT wire between the main relay and the ECM 15A fuse.

It seems like your problem is along these lines, if you have total confidence in your ECM.

TxGreaseMonkey
Sep 13, 2006, 10:18 AM
Here's another simple test on the main relay harness:

. Turn ignition switch ON and measure the voltage between BLK/YEL terminal 5 and body ground.
. Is there battery voltage? NO--Replace ACG (ALT)(S) (15 A) fuse in the under-dash fuse/relay box or repair open in the BLK/YEL wire between the main relay and the ACG (ALT)(S) (15 A)fuse.

Darvin, if you read voltage, probably around 12.5 v. then your first relay should click. If the previous test showed voltage at terminal 1, then the second relay should also work and click (if ECM and wiring is good).

Another test is to install a jumper wire on the number 5 and 7 terminals of the main relay connector and turn the ignition key ON--you should hear the fuel pump run.

If all of these tests are OK, then I think we are back to the ECM or an open between the main relay and the ECM.

Terminal 8 is a computer-controlled "grounding terminal" to the second relay. If the ECM is bad, or the wiring harness to the ECM has an open, the second relay won't ground and click, the Check Engine Light will stay on, the fuel injectors won't receive power, and the fuel pump won't run.

davin
Sep 13, 2006, 12:42 PM
Here's another simple test on the main relay harness:

. Turn ignition switch ON and measure the voltage between BLK/YEL terminal 5 and body ground.
. Is there battery voltage? NO--Replace ACG (ALT)(S) (15 A) fuse in the under-dash fuse/relay box or repair open in the BLK/YEL wire between the main relay and the ACG (ALT)(S) (15 A)fuse.

darvin, if you read voltage, probably around 12.5 v., then your first relay should click. If the previous test showed voltage at terminal 1, then the second relay should also work and click (if ECM and wiring is good).

Another test is to install a jumper wire on the number 5 and 7 terminals of the main relay connector and turn the ignition key ON--you should hear the fuel pump run.

If all of these tests are OK, then I think we are back to the ECM or an open between the main relay and the ECM.

Terminal 8 is the "grounding terminal" to the second relay, which is controlled by the ECM. If the ECM is bad, or the wiring harness to the ECM has an open, the second relay won't click, the Check Engine Light will stay on, the fuel pump won't run, and the engine won't spark.


Black/yellow and body ground register at a steady 0.014v DC

Now on other articles it states that their CEL, oil & battery stay on. However, it is only my oil and CEL that are lit and not my battery. I think there is something problematic with that possibly. I will research a little more...

TxGreaseMonkey
Sep 13, 2006, 12:56 PM
Did you have ignition ON, when you registered a steady .014 DCV? If you did, then there's your problem. You should record around 12.5 DCV. That's why your first relay won't click and everything shuts down. Check the ACG (ALT) (S) (15 A) fuse in the under-dash fuse/relay box and check for an open in the BLK/YEL wire between the main relay and the ACG (ALT) (S) (15 A) fuse.

ACG (S) stands for Alternator, Cruise control, Gauges, and SRS unit (VB) fuse.

TxGreaseMonkey
Sep 13, 2006, 01:22 PM
You might have missed this fuse because, on my 1993 Civic DX, it's located to the very top right of the under-dash fuse box and next to the SRS fuse, which has an open yellow cover on it.

The flow on this circuit appears to be from the under-hood (50 A) fuse, to the ignition switch, to the under-dash fuse/relay box fuse no. 12 or 24 (15 A), to the main relay. Your problem lies along this path.

davin
Sep 13, 2006, 01:54 PM
Did you have ignition ON, when you registered a steady .014 DCV? If you did, then there's your problem. You should record around 12.5 DCV. That's why your first relay won't click and everything shuts down. Check the ACG (ALT) (S) (15 A) fuse in the under-dash fuse/relay box and check for an open in the BLK/YEL wire between the main relay and the ACG (ALT) (S) (15 A) fuse.

So I need to look at the alternator fuse, fuse #15, if I cannot find a break in the wire? Also I was thinking of checking continuity of the dizzy, would this be the white wire?

TxGreaseMonkey
Sep 13, 2006, 01:58 PM
I don't think you need to worry about the distributor for this problem. It's not fuse #15, but a 15 amp fuse that goes to the alternator and ECM. It should be marked on the under-dash fuse box cover. Should be fuse no. 12 (without SRS) and fuse no. 24 (with SRS).

I normally turn ignition ON, set DMM to DCV, and touch leads to test points on top of fuse. If I disconnect the battery, I set my DMM on audible ohms and check all under-hood and under-dash fuses in a couple on minutes.

TxGreaseMonkey
Sep 13, 2006, 02:18 PM
Since you have an automatic transmission, I hope the neutral position switch isn't the cause of all of your problems--just a thought in passing. This interlock would interfere with the main relay and ECM. I'm sure you placed your car in "Park."

davin
Sep 13, 2006, 02:39 PM
I don't think you need to worry about the distributor for this problem. It's not fuse #15, but a 15 amp fuse that goes to the alternator and ECM. It should be marked on the under-dash fuse box cover. Should be fuse no. 12 (without SRS) and fuse no. 24 (with SRS).

I normally turn ignition ON, set DMM to DCV, and touch leads to test points on top of fuse. If I disconnect the battery, I set my DMM on audible ohms and check all under-hood and under-dash fuses in a couple on minutes.

OK, well I am at work and I know that for a fact I do not have any fuses in #24 (I love photographic memory). Also know that at the #24 spot there is a picture of a fan embezzeld on the fuse fan where this is located.

TxGreaseMonkey
Sep 13, 2006, 02:48 PM
Does your Civic have air bags (SRS)?

I've meant to ask you has battery acid damaged your under-hood fuse box?

Anyhow, in my mind, we are back looking at a fuse, ignition switch, under-dash fuse box, or main relay harness issue. Do you agree?

davin
Sep 13, 2006, 02:50 PM
I don't think you need to worry about the distributor for this problem. It's not fuse #15, but a 15 amp fuse that goes to the alternator and ECM. It should be marked on the under-dash fuse box cover. Should be fuse no. 12 (without SRS) and fuse no. 24 (with SRS).

I normally turn ignition ON, set DMM to DCV, and touch leads to test points on top of fuse. If I disconnect the battery, I set my DMM on audible ohms and check all under-hood and under-dash fuses in a couple on minutes.
OK, well I am at work and I know that for a fact I do not have any fuses in #24 (I love photographic memory). Also I know that at the #24 spot there is a picture of a fan embezzeld on the fuse fan where this is located and I do have SRS. I hope I did not "nuke" it (a term in the navy of the nuclear people for nuclear-power subs that work these spaces, they think so complexed that they never think of the simple things) and totally overlook this fuse. But how was I driving all this time without it :-/

davin
Sep 13, 2006, 03:01 PM
I do not have a #24 fuse and I do have airbags...

TxGreaseMonkey
Sep 13, 2006, 03:03 PM
On my Civic, the fuse you need to check is just to the left of the SRS fuse. My under-dash fuse box cover refers to it as the ACG (S) fuse, part of the SRS Fuse Block. There's a yellow plastic cover, with an opening in it, over the SRS fuse (No. 25), next to it.

davin
Sep 13, 2006, 03:12 PM
I only have a 10a fuse with a yellow cover and to the left of that is no fuse

TxGreaseMonkey
Sep 13, 2006, 03:15 PM
Does the fuse box cover refer to a fuse as the ACG fuse? Should be 15 A.

davin
Sep 13, 2006, 03:18 PM
When I bought the car, there was no cover. The only reference I have of "location #24" is an embezzeld fan on that spot and I do have airbags

TxGreaseMonkey
Sep 13, 2006, 03:21 PM
So you are confident you didn't overlook any fuse? If you didn't, then it must be in the harness or ignition switch.

You definitely should read around 12.5 volts from Terminal 5 on the main relay connector, when the ignition is ON. That's the issue.

The fuse may also be labeled ALT.

davin
Sep 13, 2006, 03:23 PM
I checked all the fuses to see if they where broken, but I never checked to see if any where completely missing. I will buy a 15a fuse when I go home, put it in location 24 and see what happens

TxGreaseMonkey
Sep 13, 2006, 03:27 PM
There should be 4 spare fuses in the under-dash fuse box. Normally, the extras are at the end of each row of fuses. One at the end of each row on the left and one at the end of each row on the right.

davin
Sep 13, 2006, 03:29 PM
Just to make sure, location #24 is the second to last fuse from the top right... is this correct?

TxGreaseMonkey
Sep 13, 2006, 03:34 PM
Yes.

TxGreaseMonkey
Sep 13, 2006, 04:07 PM
This might help:

http://www.honda-tech.com/zerothread/1736267

Scroll way down and you will see the under-dash fuse layout. Look for the ACG (S).

TxGreaseMonkey
Sep 13, 2006, 04:20 PM
You might find it useful to know that power for Terminal 5 comes from the IGN 1 position on the ignition switch.

davin
Sep 13, 2006, 04:35 PM
VROOM VROOM!!

OK, so I just replaced a $700 15a fuse in location #24 and now I am thinking it was someone at work screwing with me because we have a back and forth game where we mess with peoples things. Well, what I am thinking is someone took my #24 fuse and completely forgot to tell me. I mean, how else would this fuse be completely missing.

I replaced the fuse and it started right up! I think I will start confronting people at work and see what the deal is. I have a pretty good idea as to who it might have been. Thank you for everything and I am not very happy with this person right now. This was crossing the line and payback is a *****.

I will do a write up and a trouble shooting guid for this unless you want to do it. Better yet, we both can do this if you want? Anyway, I have to head out to school with a car I can actually drive now :-D

Thank you for everything!!

TxGreaseMonkey
Sep 13, 2006, 06:57 PM
Praise the Lord! I am elated for you. Davin, do you know we worked on this for 5 days? You aren't the only one who's torqued-off at whoever did this. My guess is that it's your "buddy," who owns the other Civic, because it takes detailed knowledge to know the significance of this key fuse. This was more than a prank. In my opinion, this could be an Article 15 (Mast, in the Navy) and possibly an Article 32 violation of the Uniform Code of Military Justice. Don't retaliate and go down that path. The individual should be required to reimburse you for your expenses. This affected your readiness, your education, and your wallet in a big way.

The positive is that you now know your Civic like very few other people. You also have a new distributor, ICM, coil, distributor cap, rotor, spark plugs, main relay, and a spare ECM and ignition switch. Your Civic just got a new lease on life. Now, we can move on and talk about fun maintenance items you can perform, without so much tension and feeling of impending doom.

TxGreaseMonkey
Sep 13, 2006, 09:43 PM
Davin, go back and "baseline" your ECM, by taking a reference wire voltage check on your MAP sensor connector. Also, be sure to print a copy of the under-dash fuse/relay layout and keep it in your car.

davin
Sep 14, 2006, 04:44 PM
Davin, go back and "baseline" your ECM, by taking a reference wire voltage check on your MAP sensor connector. Also, be sure to print a copy of the under-dash fuse/relay layout and keep it in your car.

Yes, I will definitally do that. I confronted te person about it and he is going to buy me lunch for 2 weeks. He feels bad because he went home and completely forgot to tell me. The following day he was afraid to tell me because I was really upset and immediatally threw money at it. When I knew it was a prank, I confronted him and just plain said that he owes me lunch for 2 weeks. He knew I knew it was him and he said OK. We are cool now, I learned a lot and I am just trying to be optimistic about this.

Thank you for everything 4sure. I learned a lot and now I know a lot about civics so if I ever have these problems I know what to do :-D

TxGreaseMonkey
Sep 14, 2006, 05:33 PM
Glad to hear that you got everything straightened out at work. I'm sure you both feel better about it now.

How many miles do you have on your Civic?

TxGreaseMonkey
Jan 17, 2009, 11:34 AM
Davin, thought I would follow-up. Are you still in the Navy? How's your Civic running? Hope all is going well.

Your posting is still the most unforgettable one.. . What a surprise ending!